1. Field Of The Invention
The present invention relates to an air gun, for firing a bullet and performing blowback using compressed gas, and having a mechanism for both firing a bullet and performing blowback with energy supplied from compressed gas. More specifically, the structure of the air gun is more simplified compared to air guns having conventional blowback mechanisms and the air gun has a blowback mechanism that shoots a bullet and performs blows-back more effectively.
2. Description of the Related Art
A mechanism of a conventional air gun that shoots a bullet and performs blowback by compressed gas includes a magazine, a compressed air source, a slide, a cylinder, an inner barrel, a barrel body, and trigger. A valve pin is provided in a valve body air chamber that is a space containing compressed gas in the valve body. A hit pin is provided in a gun rear end side of the valve pin. The hit pin has a hammer that rotates backward by the action of the trigger. The hammer that rotates by the action of the trigger hits the hit pin to move the hit pin and valve pin towards the muzzle side of gun, causing the gas in the valve body air chamber to spout onto the valve pin to shoot a bullet and perform blowback.
An air gun that has a blowback mechanism with this construction is disclosed in U.S. Pat. No. 6,026,797 (Related Art 1) that the applicant of the present invention applied for and owns a patent right. The Related Art discloses a following air gun:
This invention can make a valve compact in function and improve usage efficiency of a compressed gas and make an air gun compact. To achieve this object, an air gun is constructed by a hit pin arranged in a cylinder portion, a valve body arranged within a hollow portion of the cylinder portion and having a bullet supplying nozzle chamber and a valve pin chamber, a gas inlet port opened to a sleeve-shaped circumferential face of the valve pin chamber, a bullet supplying nozzle arranged within the bullet supplying nozzle chamber, and a valve pin arranged within the valve pin chamber. The hit pin is pressed on a muzzle side and the valve pin is slid to the muzzle side so that an airtight state between a valve pin flange portion and a side face of the valve pin chamber on its gun rear end side is released. A compressed gas is supplied to a nozzle chamber side opening and a valve pin chamber side opening from a clearance between the valve pin flange portion and the gun rear end side face of the valve pin chamber.
Additionally, U.S. Pat. No. 7,267,119 (Related Art 2) that the applicant of the present invention applied for and owns a patent discloses as follows:
An air gun including a slide, a barrel, a cylinder portion, a hit pin, a hollow valve pin chamber, a valve body, a gas supply port, a valve pin, a pressing section, a bullet feed nozzle link connected to a trigger; and a bullet feed nozzle. When the hit pin is pressed to the muzzle side and made to slide to the muzzle side, the valve pin slides to the muzzle side against an urging force to release an airtight state between the valve pin flange section and the gun rear end side side surface of the valve pin chamber; compressed gas supplied to the valve pin chamber from the gas supply port is supplied from between the valve pin chamber gun rear end side side surface and the valve pin flange section to the valve pin chamber side opening; and a bullet is fired from the muzzle by passing compressed gas through the bullet feed nozzle insertion section a supplying to the muzzle side of the bullet feed nozzle; and compressed gas is supplied from a clearance between the pressing section and through holes into which the pressing section is inserted to the gun rear end side to cause the cylinder section to move to the gun rear end side.
A U.S. Pat. No. 7,353,816 (Related Art 3) is a divisional application of the Related Art 2 and has become common knowledge. In his technology, a gun has a structure where a cylinder that is provided in a gun rear end side of the slide capable of free movement, has a hammer and no hit pin.
Further, the applicant of the present invention applied for a patent of an air gun having a blowback mechanism with a barrel latch in Taiwan on Dec. 7, 2006 as follows (Taiwan Patent Application Number 95145714=U.S. Pat. No. A11/655,205, EPA 06027082.4) (Related Art 4):
An air gun, for firing a bullet using compressed gas, and having a mechanism for blowing back, wherein
the blowback mechanism is provided with a firing chamber and a blowback chamber, being two cavities capable of being supplied with compressed gas from a compressed gas source and being sealed to contain the compressed gas, inside a valve body, a firing valve inside the firing chamber, a blowback valve inside the blowback chamber, and two valves that are capable of actuation independent of each other by operation of a trigger.
However, an air gun with a blowback mechanism disclosed in the Related Art 1 to 4 at least has a hammer at the rear end of the gun. The hammer rotates by a trigger bar or a sear that transmits the movement of the trigger, hits a hit pin from behind and moves the hit pin and valve pin from the muzzle side of the gun to eject the gas in the valve body air chamber to the valve pin for firing a bullet and performing blowback.
Therefore, an air gun with a blowback mechanism has members such as a hammer, a sear, a trigger bar, a bullet supplying nozzle, a bullet supplying nozzle link and their fittings, making the structure complicated. The members move every time a bullet is fired so that members are likely to be worn, and the air gun is easily damaged and likely to have problems with durability.
Additionally, in an air gun with a blowback mechanism disclosed in the Related Art 1, in some cases, at first, compressed gas functions as a force to press the cylinder backward, then compressed gas starts applying power on a bullet on the muzzle side. A bullet is fired while the cylinder is retreating, and shooting a bullet during the retreat of the cylinder decreases the grouping on a target.